trac-admin repository sync/resync randomly stops syncing

[adf@…]

There are 36868 revisions in my repo.

I am trying to sync the repo after adding it, it stopped doing it after a few hundred, then after a few thousand, then it did around 22,000 and stopped, then on running again, just stoped at same point, then run again, carried on.

[root@svnmirror ~]# trac-admin /var/trac repository sync INFORMATE
Resyncing repository history for INFORMATE... 
23281 revisions cached.
Done.
[root@svnmirror ~]# trac-admin /var/trac repository sync INFORMATE
Resyncing repository history for INFORMATE... 
23281 revisions cached.
Done.

Then started again, processing revision 24240 …

[root@svnmirror ~]# trac-admin /var/trac repository sync INFORMATE
Resyncing repository history for INFORMATE... 
 [24240]

and stopped.

[root@svnmirror ~]# trac-admin /var/trac repository sync INFORMATE
Resyncing repository history for INFORMATE... 
2539 revisions cached.
Done.

Started again, but this time, its processing revision 1536??

[root@svnmirror ~]# trac-admin /var/trac repository sync INFORMATE
Resyncing repository history for INFORMATE... 
 [1536]

If I look in trac, it shows the last revision as 36868 but shows no information for those revisions.

No errors are reported, so not sure what's going on.

The server is running in a VM. CentOS 6.5 and using sqlite as the database.

There are multiple repositories configured but not all have been synchronised yet. The DB is around 120MB currently.

[Jun Omae]

Please post System Information in your Trac and trac.log with DEBUG level when executing trac-admin resync ....

[anonymous]

It's a 'database is locked' issue.

trac-admin /var/trac repository sync INFORMATE

2018-03-12 14:13:28,519 Trac[cache] INFO: Trying to sync revision [26939]
...

trac-admin /var/trac repository sync DEMA

2018-03-12 14:13:31,882 Trac[cache] INFO: repos rev [2584] != cached rev [None]
...

the DEMA sync starts processing some big revisions …

2018-03-12 14:13:34,203 Trac[cache] DEBUG: Caching node change in [5]: (u'tags/SP13/zMTSUsr.cls', 'file', 'add', None, -1)
2018-03-12 14:13:34,283 Trac[cache] INFO: Trying to sync revision [6]
2018-03-12 14:13:34,287 Trac[cache] DEBUG: Caching node change in [6]: (u'tags/SP14', 'dir', 'move', u'tags/SP13', 5)
2018-03-12 14:13:34,296 Trac[cache] INFO: Trying to sync revision [7]
2018-03-12 14:13:34,300 Trac[cache] DEBUG: Caching node change in [7]: (u'tags/SP14Plus', 'dir', 'add', None, -1)
2018-03-12 14:13:34,311 Trac[cache] INFO: Trying to sync revision [8]
2018-03-12 14:13:38,643 Trac[cache] WARNING: Revision 26939 already cached: OperationalError('database is locked',)
2018-03-12 14:13:39,292 Trac[cache] INFO: Resetting "repository_dir": svn:6bbf3ac7-fb38-469b-93a1-a286480b79be:/var/svn/products/INFORMATE
2018-03-12 14:13:39,310 Trac[cache] DEBUG: cache metadata undefined (youngest_rev=0)
2018-03-12 14:13:39,310 Trac[cache] INFO: repos rev [36830] != cached rev [None]
2018-03-12 14:13:39,312 Trac[cache] INFO: Trying to sync revision [1]
2018-03-12 14:13:40,258 Trac[cache] DEBUG: Caching node change in [8]: (u'tags/SP14Plus/1', 'file', 'add', None, -1)

I can work around it by stopping the background tasks while I do the initial resyncs.